Biomedical subjects

P Costello

Publications and source records attributed to P Costello.

At least 19 recordsLinked to original sources

PubMed1992

Evaluation of three immunoassays for detection of Chlamydia trachomatis in urine specimens from asymptomatic males.

The performances of three commercially available immunoassays (Chlamydiazyme/Antibody Blocking Assay [Abbott Diagnostics, Abbott Park, Ill.], IDEIA [Analytab Products, Plainview, N.Y.], and Microtrak EIA [Syva Co. Palo Alto, Calif.]) were evaluated for the detection of Chlamydia trachomatis in urine specimens from asymptomatic males. Assay results were compared with direct specimen immunofluorescence (DFA) analysis of urine sediment (Syva Microtrak; Syva Co.), which was chosen as the study confirmation assay. An overall Chlamydia prevalence of 7% (24 of 340) was found in our study population, with peak incidences occurring in the adolescent (8 of 93 specimens) and young adult (11 of 146 specimens) age groups. Sensitivity and specificity data among the Chlamydiazyme, IDEIA, and Microtrak enzyme immunoassays (EIAs) were determined to be 79.1 and 99%, 91.7 and 98%, and 95.8 and 99%, respectively. The Microtrak EIA and IDEIA products demonstrated sensitivities and specificities equal to or greater than those claimed for urine specimens. The diagnostic accuracies of these assays on asymptomatic subjects, along with the ease of this collection method, suggest a role for these products as screening tools. The sensitivity of the Chlamydiazyme assay was lower than that claimed previously in symptomatic patients, with 5 of 24 positive specimens demonstrating false-negative results. In those cases, centrifugation of the original immunoassay aliquot material and then DFA examination confirmed specimen positivity. Urine immunoassay screening in combination with DFA confirmation (which was chosen because it has antibody epitopic specificity different from that of the primary assay) provides a high degree of diagnostic precision. The use of noninvasive collection methods could result in greater testing compliance among asymptomatic males and, subsequently, could reduce the incidences of both symptomatic and silent chlamydial infections.

Adolescent↗

PubMed1992

Spiral CT in evaluation of head and neck lesions: work in progress.

Spiral computed tomography (CT) was used in the evaluation of 21 patients with head and neck lesions. Scanning time ranged from 24 to 36 seconds, and high-quality diagnostic scans with excellent anatomic resolution and minimal motion artifact were produced. Vascular opacification was optimized with substantially less contrast medium than used in conventional studies. These preliminary results show spiral CT to be at least comparable with conventional CT in the evaluation of the head and neck.

Female↗

PubMed1992

Spiral CT of the thorax with reduced volume of contrast material: a comparative study.

The effectiveness of spiral computed tomography (CT) of the thorax performed with 60 mL of 60% contrast material was compared with that of conventional dynamic incremental CT performed with 120 mL of 60% contrast material. Fifty patients in whom contrast material-enhanced thoracic CT examination was necessary were assigned to undergo either spiral CT or dynamic incremental CT. Vascular opacification and mediastinal-lung image quality were graded independently by two observers. Vascular opacification and lung image quality were better with spiral CT than with conventional CT. Results of this pilot study encourage the use of spiral CT to decrease the volume of contrast medium used in patients undergoing thoracic CT.

Adult↗

PubMed1992

Spiral CT of the pancreas.

Computed tomography (CT) is the modality of choice for evaluation of pancreatic disease. In this prospective study, images obtained with spiral CT, which enables examination of a region of the body in a single breath-hold, were compared with those obtained by means of dynamic CT with automatic table incrementation in two groups of 30 patients referred for suspected disease of the pancreas. In both groups, vascular opacification and anatomic detail were analyzed with a grading system (1 = poor, 2 = good, 3 = excellent). Vascular opacification received mean grades of 2.78 and 2.33 in the spiral CT and control groups, respectively. Anatomic detail received mean grades of 2.63 and 2.42 in the spiral CT and control groups, respectively. Respiratory motion artifact was absent in all spiral CT examinations but was present in 17 of 30 control CT examinations. Images obtained with spiral CT showed superior vascular opacification and reduced respiratory artifact with smaller amounts of contrast agent (90 mL vs 120 mL) compared with those obtained with dynamic CT.

Adult↗

PubMed1992

Assessment of the thoracic aorta by spiral CT.

A recently developed technique, spiral CT, allows rapid data acquisition through an entire anatomic region during a single breath-hold. High-quality spiral CT scans of the thoracic region have been obtained with volumes of contrast material that are small relative to those used with conventional CT. This essay illustrates the diseases of the aorta as seen on spiral CT performed with low volumes of contrast material.

Aged↗

PubMed1992

Noninvasive liver imaging: new techniques and practical strategies.

The goals and expectations of liver imaging have expanded as the treatment options for a range of liver diseases have advanced. Unfortunately, no single modality can yet achieve all the goals that an ideal imaging modality should satisfy. Currently available liver imaging techniques should be considered complementary rather than competitive in their roles, and appropriate utilization of the expanding technical capabilities of cross-sectional imaging depends on many considerations, including patient factors, referring physician expectations and biases, experience and bias of the radiologist, and the availability of state-of-the-art technical capabilities for each modality. This article reviews the advantages, limitations, and roles of fast CT and fast MR liver imaging techniques as well as the complimentary role of ultrasound, and the future of new imaging considerations including the role of contrast agents.

Humans↗

PubMed1992

Cross-sectional imaging of liver transplantation.

Orthotopic liver transplantation is commonly performed at many institutions around the world. The care of these critically ill patients has heavily relied upon cross-sectional imaging. CT, MRI, and ultrasound help enormously in the preoperative assessment of these patients and in the postoperative management of the various complications. This article reviews the role of these cross-sectional modalities and their respective strengths and weaknesses in the adult transplant candidate and recipient.

Humans↗

PubMed1991

Pulmonary nodule: evaluation with spiral volumetric CT.

Spiral volumetric computed tomography (CT) was used prospectively in 20 patients with a suspected solitary pulmonary nodule less than 1 cm in diameter on plain chest radiographs. Four additional nodules were detected with spiral CT than were detected with conventional CT. This technique required a 12-second breath hold; patient cooperation was excellent.

Humans↗

PubMed1991

Abdominal CT findings after liver transplantation in 66 patients.

CT scanning is used frequently to assess the condition of patients after liver transplantation. The CT records of 174 adult patients who underwent liver transplantation were studied retrospectively to determine the number and timing of CT studies as well as the frequency and significance of the findings. One-hundred seventy CT scans were obtained in 66 (38%) of the 174 patients, with a mean of 2.6 scans/patient. The interval between transplantation and scanning was 1 day to 24 months; in 59 (89%) of 66 patients, the first CT scan was obtained within 30 days. The acute indications for CT scanning were fever or leukocytosis in 54 (92%) of 59 patients and abnormal liver function tests in five (8%) of 59 patients. CT scans obtained more than 30 days after transplantation were repeat scans in all but seven patients. Indications in this latter group were the same as for the acute group, plus evaluation of hepatic neoplasia in three patients. CT findings included periportal low attenuation in 41 (62%) of 66 patients; ascites in 25 (38%); splenomegaly in 19 (29%); loculated intraperitoneal noninfected fluid collections in 13 (20%); intrahepatic, splenic, pancreatic, or perihepatic abscesses in seven (11%); hepatic infarction in six (9%); splenic infarction in three (4%); and hepatic calcification in two (3%). Other major abnormalities included inferior vena caval thrombosis (one patient), pseudoaneurysm of the hepatic artery with rupture (one patient), and recurrent hepatocellular carcinoma (one patient). CT scanning after liver transplantation is used predominantly in the acute setting to evaluate for liver infarction or intraabdominal abscess. In this setting, CT showed these abnormalities, in addition to tumor recurrence or vascular abnormalities, in 15 (23%) of 66 patients.

Ascites↗

PubMed1990

Human cerebral endothelium: isolation and characterization of cells derived from microvessels of non-neoplastic and malignant glial tissue.

Human microvessels were isolated and cultured from non-neoplastic cerebral tissue specimens resected for the treatment of seizure disorders and from malignant glial tumors. After 1-2 weeks, cobblestone patterned plaques of cells were isolated and cultured from these microvessels. Cell lines positive for Factor VIII antigen and negative for glial fibrillary acidic protein were designated as endothelium. Endothelium from both tissue sources produced gamma-glutamyl transpeptidase in response to glial cell conditioned media. Tumor derived microvessel endothelium had decreased longevity in culture when compared to normal microvessel endothelium. Tumor derived endothelium also formed less extensive intercellular junctional complexes in vitro. The isolation and characterization of human cerebral microvessel endothelium derived from non-neoplastic tissue and glial tumors may lead to a further understanding of the role of endothelium in tumor growth and vascular permeability alterations.

Adolescent↗

PubMed1990

Cytomegalovirus in the brain: in vitro infection of human brain-derived cells.

Models for human cytomegalovirus (HCMV) brain infection have been developed in a variety of brain-derived cells in which the factors governing virus infectivity might be studied in vitro. Studies were initiated with brain endothelial cells, the likely portal of entry for virus into the central nervous system. Primary explant cultures of brain endothelial cells, derived from homogenates of healthy human brain, supported complete viral gene expression and cytopathic effect (CPE). Endothelial cells do not appear to be a barrier for HCMV passage into the central nervous system. Astroglial lines (primary explant or tumor-derived) varied in their ability to support HCMV replication. Some (T98G) supported incomplete (immediate-early) gene expression while others (A-172) did not support any detectable gene expression. Some astroglial lines (HS-683) supported extensive virus replication with minimal viral CPE. Neuronal cell lines (SK-N-MC) were fully permissive. The more differentiated glial lines (astrocytoma) were fully permissive to HCMV infection; however, the less differentiated glial lines (glioblastoma) were partly or nonpermissive.

Astrocytes↗

PubMed1989

Dose-dependent inhibition of theophylline metabolism by disulfiram in recovering alcoholics.

The influence of disulfiram on theophylline metabolism was studied in 20 recovering alcoholics. Ten of the patients, who were selected at random, received 250 mg of disulfiram daily. The other 10 patients received 500 mg of disulfiram daily. Two single-dose studies of theophylline kinetics were performed--one as a baseline control and the other after 1 week of treatment with disulfiram. With disulfiram pretreatment, the plasma clearance of theophylline was decreased from 105.7 +/- 10.2 (mean +/- SEM) to 83.1 +/- 8.1 ml/kg per hour (p less than 0.001) in the 250 mg group and from 94.3 +/- 13.3 to 65.4 +/- 10.7 ml/mg per hour (p less than 0.001) in the 500 mg group. The elimination half-life was prolonged significantly in both groups. The percent reduction in theophylline clearance was greater in the 500 mg group (32.5 +/- 3.1; range, 21.6 to 49.6) than it was in the 250 mg group (21.2 +/- 1.7; range, 14.6 to 29.6; p less than 0.01). Disulfiram decreased the formation of all theophylline metabolites in smokers in both treatment groups. In each group, the hydroxylation pathway was affected more than the demethylation pathway. These data indicate that at therapeutic doses disulfiram exerts a dose-dependent inhibitory effect on theophylline metabolism. Depending on the dose of disulfiram, a dose reduction of theophylline by as much as 50% may be necessary to minimize the risk of toxicity.

Adult↗

PubMed1988

Sensitivity of rhabdomyosarcoma and guinea pig embryo cell cultures to field isolates of difficult-to-cultivate group A coxsackieviruses.

Forty-two difficult-to-cultivate group A coxsackieviruses (i.e., group A types other than A7, A9, and A16), collected primarily from throat swab specimens of patients suffering from fever, pharyngitis, lymphadenopathy, and cough during the 1986 enterovirus season, were isolated in less than 24-h-old suckling mice. Thirty-six moribund mice were sacrificed and autopsied, and then their brains and back musculature were inoculated into rhabdomyosarcoma (RD), guinea pig embryo (GPE), rhesus monkey kidney (RhMk) and human carcinoma of the larynx (HEp-2) cell cultures. Twelve of the 36 suckling mice isolates were adapted to grow in RD and GPE cells after two passes and have been identified in RD cells by type-specific antisera as group A coxsackievirus types A2, A4, and A8. Three passes in RhMk or HEp-2 cell cultures were insufficient to affect a discernible cytopathic effect. Coxsackievirus types A1, A19, and A22, unable to grow in any of the four cell cultures tested, were identified by virus neutralization in suckling mice. These data denote the efficacy of suckling mice for the isolation of difficult-to-cultivate group A coxsackieviruses.

Animals↗

PubMed1988

CT-guided aspirations for the body: comparison of hand guidance with stereotaxis.

Forty computed tomography (CT)-assisted aspirations performed with only hand guidance were prospectively compared with 40 performed with a CT body-stereotaxic system. Although there was no statistically significant difference in lesion size and path length between the two groups, use of stereotaxis compared with hand guidance decreased by 75% the number of needle manipulations required to place a needle within a lesion. With the stereotaxic method, only 43 needle manipulations were required to confirm a needle placement in 40 lesions, with no lesion requiring more than two attempts. Use of stereotaxis decreased the number of localization scans by 80% and biopsy time by 50%. It is concluded that CT-guided needle placements with hand guidance are often inaccurate and, unless the lesion is large, require multiple needle manipulations to place a needle within the lesion. Stereotaxis-guided biopsies, on the other hand, decrease radiation exposure, biopsy time, and trauma from multiple needle punctures.

Biopsy, Needle↗

PubMed1988

Unilateral absence of the external carotid artery.

We report a patient with absence of the external carotid artery. The major external branches originate from the internal carotid artery which is really a common arterial trunk. The embryology and clinical significance of this rare vascular anomaly are discussed.

Adult↗

PubMed1987

Isolation and culture of cells derived from human cerebral microvessels.

Microvessels were isolated from non-neoplastic human cerebral cortical fragments resected for treatment of intractable seizure disorder. The microvessels were incubated in modified Lewis medium with 20 or 30% fetal bovine serum. Within 1-2 weeks, two cell populations emerged from the isolates. One type of cells had polygonal morphology, showed density-dependent contact inhibition at confluence in vitro, showed lectin-binding characteristics of endothelium (but only moderate positivity for factor VIII antigen), demonstrated induction of gamma-glutamyl transpeptidase when exposed to astrocyte-conditioned media, and responded to insulin by a pronounced increase in DNA synthesis. The other variety of cells grew in vitro more slowly in irregular strands separated by clear zones, showed ultrastructural features of smooth muscle, and isoelectric focusing of cell proteins revealed the presence of smooth-muscle-specific alpha-isoactin. Both types of cells could be serially subcultured. The ability to isolate and grow the two cell types, tentatively identified as human cerebral microvascular endothelium and smooth muscle, may facilitate studies of human blood-brain barrier function as well as the pathogenesis of cerebral microangiopathies unique to the human brain.

Adolescent↗

PubMed1987

CT body stereotaxic system for placement of needle arrays.

A new CT body stereotaxic system that is particularly suited to multiple placements of needles precisely in parallel is described. By scanning through a right triangle placed on the patient's skin, the stereotaxic method defines an entry point for the first needle placement. An articulating arm is then used to aim the needle at the entry point and hold the needle at the correct angle. The arm can be angled so that the complex approaches from one scan plane to another can be made to place needle arrays through inaccessible lesions, for instance, beneath the diaphragm. Animal and phantom studies have shown that placement of multiple needle arrays in parallel from CT scan data is possible.

Biopsy, Needle↗

PubMed1987

Computed tomographic--guided stereotaxic biopsy of thoracic lesions.

A stereotaxic guidance system has been used in conjunction with a conventional CT unit to biopsy 26 consecutive thoracic lesions. Accurate needle placement with a single manipulation occurred in 24 instances and two lesions required second passes. The technique provided adequate pathologic material with an acceptable complication rate. System advantages include the ability to approach lesions along oblique paths, controlled approach in difficult locations (mediastinal, peripheral, subscapular), capacity to biopsy small nonfluoroscopically visualized lesions, and increased speed over manual techniques.

Biopsy, Needle↗